Question:
Mark $(\sqrt{)}$ against the correct answer in each of the following:
$\int \sqrt{1-9 x^{2}} d x=?$
A. $\frac{x}{2} \sqrt{1-9 x^{2}}+\frac{1}{18} \sin ^{-1} 3 x+C$
B. $\frac{3 x}{2} \sqrt{1-9 x^{2}}+\frac{1}{6} \sin ^{-1} 3 x+C$
C. $\frac{x}{2} \sqrt{1-9 x^{2}}+\frac{1}{6} \sin ^{-1} 3 x+C$
D. none of these
Solution:
